ALBERT

Notes: Field studies were conducted in 1988 and 1989 to determine the phenology and growth of broomrape in sunflower as affected by crop sowing dates. The parasitic weed attachment was observed in sunflower plants with 6–7 leaves; later it was found throughout the vegetative and flowering period of the crop. O. cernua seedlings with shoot development extensive but subterranean were mainly observed at the early heading stage of sunflower. At this stage they were beginning to reduce sunflower plant growth as compared with non–parasitized plants. The emergence of broomrape began at the early flowering stage of the crop and was particularly abundant throughout this and the achene–filling stage. Generally, broomrape infection was much less at the first than at the second or third sunflower sowings, and caused less reduction in yield.The duration of the broomrape emergence period increased as sowing date was delayed. Since sunflower yield was higher at earlier sowing dates, early sowing may be recommended for sunflower crops in broomrape–infested areas under mild mediterranean climates. Effet de la date de semis sur les infections d'orobanche (Orobanche cernua Loefl.) en culture de tournesol (Helianthus annuus L.)Des études de plein champ ont été conduites en 1988 et 1989 pour déterminer comment la phénologie et la croissance des orobanches en culture de tournesol étaient affectées par les dates de semis de la culture. Le rattachement de 1'adventice parasite a été observeé chez les plantes de tournesol avec 6–7 feuilles; plus tard il était observé tout au long des périodes végétatives et de floraison de la culture.Des plantules d'O. cernua avec un développement de la tige important mais souterrain ont été principalement observées au stage bourgeon précoce du tournesol. A ce stade elles ont commencé & réquire la croissance du tournesol en comparaison avec des plantes non parasitées. La levée de 1'orobanche a commencé au début du stade de la floraison de la culture et a été particuliérement abondant pendant celle–ci et le stade remplissement des akénes. Généralement, l'infection d'orobanche a été beaucoup moins forte au premier qu'au second et troisiéme semis et a causé des baisses de rendement plus faibles.La durée de la période de levée des orobanches a augmenté quand le semis a été retardé. Puisque le rendement en tournesol a été plus élevé pour les dates de semis précoces, un semis précoce peut être recommandé pour le tournesol en zones infestées par les orobanches sous les climats méditerranéens. Die Bedeutung des Saattermins der Sonnenblume (Helianthus annuus L.) für den Befall mil der Sommerwurz (Orobanche cernua Loefl.) In Feldversuchen wurden 1988 und 1989 die PhÄnologie und das Wachstum der Sommerwurz in Sonnenblumenkulturen untersucht. Der Befall der Sonnenblumenpflanzen wurde im 6- bis 7-Blatt-Stadium festgestellt, aber auch später in der gesamten vegetativen und generativen Phase der Kulturpflanze. Keimpflanzen der Sommerwurz mit einer kräftigen, aber unterirdischen Sproßentwicklung wurden überwiegend im frühen Stadium der Blütenentwicklung der Sonnenblume beobachtet. In diesem Stadium begann die Wachstumshemmung der Sonnenblume. Zu Beginn der Blüte der Sonnenblume lief die Sommerwurz auf und war während dieses Entwicklungsstadiums und der folgenden Samenbildung besonders häufig anzutreffen. In der ersten Aussaat der Sonnenblume war der Befall allgemein geringer als in der zweiten oder dritten. Mit späterem Saattermin verlängerte sich die Keimungsperiode der Sommerwurz. Nachdem die Sonnenblume bei früherer Saat einem höheren Ertrag brachte, wird für mild-mediterrane Gebiete mit Befall von Sommerwurz eine frühe Aussaat empfohlen.

Notes: Abstract. The repeated application of pig slurry to agricultural soils may result in an accumulation of salts and a risk of aquifer pollution due to nitrate leaching and salinization. Under Mediterranean conditions, a field experiment on a sandy loam soil (Typic Xerofluvent) was performed with maize (Zea mays) in 1998, 1999 and 2001 to study the effects of applying optimal (P1) and excessive rates (P3) of pig slurry on soil salinization, nitrate leaching and groundwater pollution. The rate of pig slurry was established considering the optimal N rate for maize in this soil (170, 162 and 176 kg N ha−1 for 1998, 1999 and 2001, respectively). Pig slurry treatments were compared to an optimal N rate supplied as urea (U) and a control treatment without N fertilizer (P0). The composition of the slurries showed great variability between years. Mean NO3− leaching losses from 1998 to 2001 were 329, 215, 173 and 78 kg N ha−1 for P3, P1, U and P0 treatments, respectively. The amount of total dissolved salts (TDS) added to the soil in slurry application between 1998 and 2001 was 2019 kg TDS ha−1 for the P1 treatment and 6058 kg TDS ha−1 for the P3 treatment. As a consequence, the electrical conductivity (EC) of the slurry-treated soils was greater than that of the control soil. The EC correlated significantly with the sodium concentration of the soil solution. Over the entire experimental period, 2653, 2202 and 2110 kg Na ha−1 entered the aquifer from the P3, P1 and P0 treatments, respectively. The P3 treatment did not significantly increase grain production in 1999 and 2001 compared with that achieved with the optimal N rate treatment (P1). This behaviour shows the importance of establishing application guidelines for pig slurry that will reduce the risk of soil and groundwater pollution.

Notes: The M-92 technique is aimed at helping teenagers become aware of: (a) the relationships between certain classic determinants such as prestige, income, and job opportunities and their system of job aspirations and/or expectations; (b) the strong and weak points in their system of information about jobs; (c) the internal structure of their system of occupational representations; and (d) possible conflicts in values or discordancies between aspirations and expectations. From a theoretical standpoint the M-92 draws directly on Coombs (1975) and Gottfredson (1981). Methodologically, it is an extension of the Hammond et al. (1988) Social Judgement Theory to the case of pair comparisons. Several concrete examples of the M-92 in use are described.

Notes: Oxidation of dihydrocapsaicin (8-methyl-N-vanillyl-6-nonanamide) by peroxidase (EC 1.11.1.7) from Capsicum annuum var. annuum fruits yielded one absorbent oxidation product with E262= 4.7 103 M−1 cm−1. Dependence of oxidation rate on dihydrocapsaicin and H2O2 concentrations revealed Michaelis-Menten type kinetics with inhibition at high substrate concentrations and optimal pH near 6.0. Dihydrocapsaicin was oxidized by pepper peroxidase, and participation of peroxidase in capsaicinoid metabolism of pepper fruits should be taken into account.

Notes: Although Mycobacterium marinum and Mycobacterium tuberculosis are very closely related they differ significantly in their growth rates. The Type strain of M. marinum and one clinical isolate were investigated and, like M. tuberculosis, were found to have a single rRNA (rrn) operon per genome located downstream from murA gene and controlled by two promoters. No sequence differences were found that account for the difference in the growth rates of the two species. We infer that M. tuberculosis has the capacity to synthesize rRNA much faster than it actually does; and propose that the high number of insertion sequences in this species attenuate growth rate to lower values.

Notes: We report here the identification of an ornithine decarboxylase (ODC) gene in the putrescine-producer Oenococcus oeni BIFI-83 strain. The gene contains a 2,235-nucleotide open reading frame encoding a 745-amino acid residues protein with a deduced molecular mass of 81 kDa. The primary structure of the ODC deduced from the nucleotide sequence has a consensus sequence containing the pyridoxal-5-phosphate (PLP) binding domain, and the critical amino acids residues involved in enzymatic activity are also conserved. As determined by BLAST analysis, the deduced amino acid sequence of the odc gene shares a 67% identity with the ODC protein from Lactobacillus 30a. The odc gene appears to be rarely present in the genome of O. oeni, since in a screening for the presence of this gene in 42 oenococcal strains none of the strains possessed an odc gene copy.

Notes: Abstract: The bioleaching of a low-grade uranium ore in shaker and columns using natural, pure and mixed cultures has been studied. Initially, a chemical and microscopical characterization of the mineral was carried out. Orbital shaker experiments were performed to quickly obtain the best bacterial leaching conditions. Afterwards, small columns were used to determine other variables related to percolation leaching. Finally, an uranium ore from the F6 mine (Ciudad Rodrigo, Spain) was leached in the presence of bacteria using large columns (24 cm diameter and 275 cm height). The most important results were: (i) the ore contains sufficient pyrite in order for uranium bioleaching to take place under optimum conditions; (ii) shaker experiments showed that temperature, pH and type of inoculum are the most important variables in bioleaching; (iii) two different ores were attacked in the columns: altered and non-altered. In the first case, the extraction rate of uranium was higher. However, in both cases the final efficiency was very similar (95%).